Mozilla has long considered itself a champion of the free and open Web, and the company plans to walk the walk as much as it talks the talk. The company's latest and best foot forward in that direction: Lightbeam for Firefox.

This Firefox add-on shows, graphically, how the sites you visit interact with other sites -- and how tracking information may be gathered in the process, often from multiple sites at once without your knowledge.

Many of us know casually that browsing a given site also means interacting invisibly with a whole slew of other sites. Facebook, for instance: there's barely a site that doesn't invoke code from Facebook's servers for the sake of the Like button, Comment forms, and so on. Lightbeam aims to make it clearer how all that works.

Originally developed as a project code-named Collusion, Lightbeam presents the user with three basic ways to slice and dice the data gathered from your movements online. The Graph view lets you see how any given site visited interacts with others -- and lets you see which sites have the most, or least, interactions with other sites. Clock view lets you see how many connections are made hour-by-hour over a 24-hour period, and List view presents all connections in a flat textual list.

Other app/service combos like Ghostery have been introduced in the past to help end-users find out who's tracking them, but haven't sported anything like Lightbeam's visuals.

Alex Fowler, leader of privacy and public policy efforts at Mozilla, called it "a Wizard of Oz moment for the Web, where users can collectively pull back the curtain see its inner-workings."

What's most interesting about Lightbeam is how users can opt-in to allow the data collected about their movements to be shared with Mozilla. This sharing is off by default, and according to the Belfast Telegraph and RT.com the data submitted by Lightbeam is kept as anonymous as possible. IP addresses are not logged, data is aggregated anonymously, and the plug-in itself is open source under multiple licenses (MPL 1.1/GPL 2.0/LGPL 2.1) and can be removed easily. One imagines Mozilla is at least trying to not recapitulate many of the sins of the very people it's criticized.

Worries about how vulnerable everyday software is to tracking and surveillance, whether by government agencies or businesses looking for behavior data to mine and monetize, aren't like to dissipate anytime soon. Mozilla in particular has been hammering hard on end-user privacy. It recently upgraded Firefox to remove vulnerabilities that allowed the NSA to de-anonymize those using the Tor network, and has voiced constant concerns about the way the Web is being turned into a tool for casual wiretapping.

What's tougher to do is to raise consciousness about the issues in a way that will allow ordinary users to take proactive action. Even though the casual corporate mining of behavior data is far more pervasive than government surveillance, the latter inspires far more ire. Maybe having a tool like Lightbeam to show people the truth of the matter will be more helpful than mere words.